Long Noncoding RNA lncNDEPD1 Regulates PD-1 Expression via miR-3619-5p in CD8+ T Cells
Shaoyan Cheng, Feng Li, Haiming Qin, Yu P, Qitai Zhao, Qun Gao, Mengjia Song, Jiao Qu, Jiqi Shan, Kai Zhang, Zhen Zhang, Jingyao Lian, Shasha Liu, Liping Wang, Yi Zhang
Abstract
Abstract Therapies targeting programmed cell death protein 1 (PD-1) have gained great success in patients with multiple types of cancer. The regulatory mechanisms underlying PD-1 expression have been extensively explored. However, the impact of long noncoding RNAs on PD-1 expression remains elusive. In this study, we identified the Notch1/lncNDEPD1 axis, which plays a critical role in PD-1 expression in human CD8+ T cells. RNA sequencing and quantitative reverse transcription PCR data showed that lncNDEPD1 was upregulated in activated T cells, especially in PD-1high subsets. Fluorescence in situ hybridization demonstrated that lncNDEPD1 was localized in the cytoplasm. A mechanistic study showed that lncNDEPD1 could bind with miR-3619-5p and PDCD1 mRNA to prevent PDCD1 mRNA degradation and then upregulate PD-1 expression. A chromatin immunoprecipitation assay showed that Notch1 directly binds to the promoter of lncNDEPD1 instead of PDCD1. Furthermore, chimeric Ag receptor T cells expressing lncNDEPD1-specific short hairpin RNAs were generated. Chimeric Ag receptor T cells with decreased lncNDEPD1 expression showed enhanced tumoricidal effects when PD-L1 was present. Our work uncovered a new regulatory mechanism of PD-1 expression and thus provided a potential target to decrease PD-1 without affecting T cell function.